BAKE for 18 to 20 minutes or until wooden pick inserted in centers comes out clean. Cool in pans for 5 minutes; remove to wire racks to cool completely. Frost with Milk Chocolate Frosting.

FOR MILK CHOCOLATE FROSTING:
MICROWAVE chocolate chips, butter and salt in medium, uncovered, microwave-safe bowl on MEDIUM-HIGH power for 1 minute; STIR. The chips may retain some of their original shape. If necessary, microwave at additional 10- to 15-second intervals, stirring just until chips are melted. Transfer to large mixing bowl. Gradually beat in sugar alternately with milk. Stir in vanilla extract.